Find even fibonacci numbers

evenfib.clj

;;Returns the next even fibbonaci number
;; F[n] = 3*F[n-1] + 4*F[n-2] + 5F[n-3] + ... + (x+2)*F[n-x]
(defn evenfib-next [seq]
	(letfn getsum [seq count]
		(cond 
			(empty? seq) 0
			:else (+ 
				(* count (first seq))
				(getsum (rest seq) (+ count 1)))))
	
	(cons (getsum seq 3) seq)
)



;Output: ([8 2] (32 8 2) (138 32 8 2) (594 138 32 8 2) (2556 594 138 32 8 2) (10998 2556 594 138 32 8 2))
; 8 and 2 are the first 2 even fibbo numebers
(print (take 6 (iterate evenfib-next [8 2])))
;Want: (10998 2556 594 138 32 8 2)
;Instead of creating a list of lists, some kind of function that just appends the list